Method for making helices



A ril 13, 1965 L. KITSELMAN METHOD FOR MAKING HELICES 2 Sheets-Sheet lINVENTOR. HHRRY L. KITSELMAN, Y

I M A TTORNEYS.

April 1965 H. L. KITSELMAN 3,177,905

METHOD FOR MAKING HELICES Original Filed June 6, 1958 2 Sheets-Sheet 2INVENTOR. HARRY L. KITSEL'MAN,

A TTORNEYS.

United States Patent 3,177,9ll METHOD FDR MAKENG IELECES Harry ls.Kitsehnan, Muncie, 1nd, assignor to lndiana Steel 8r Wire Company, inn,Mannie, End, a corporation of Indiana @riginal application June 6, 1953,ger. No. 74%,451, now Patent No. 3,951,202, dated Aug. 28, 1%2. Dividedand this application July 25, 1962, Ser. No. 212,36li 5 Claims. (81.1453-91)) This invention relates to the formation of long-pitch helicesfrom relatively hard, resilient wire. Such helices frequently constituteor are embodied in splints, reinforcem nts, and supports adapted forapplication to line conductors and cables. This application is adivision of my copending application Ser. No. 740,451, filed June 6,1958, now Patent No. 3,051,202, granted August 28, 1962.

It is an object of the invention to provide a method by which suchlong-pitch helices can be simply and economically formed. Another objectof the invention is to provide a method adapted for the formation oflong-pitch helixes in portions only of a length of wire.

In carrying out my invention, I employ an elongated quill or mandrelprovided with a helical groove whose base diameter and pitch correspondgenerally to the internal diameter and pitch of the desired helix. Thewire in which the helix is to be formed is disposed in a tangentialposition in the quill-groove with the end portions of the wireprojecting obliquely in opposite directions from the quill. With one ofsuch projecting end portions secured in fixed position relative to thequill, the other end portion is wrapped about the quill into the helicalgroove. When a helix of the desired length is produced, the winding isstopped and the finished helix removed from the qu ll by unwinding ittherefrom. Conveniently, the winding is stopped while the extreme endportion of the wire remains unwound and projecting from the quill, andthe unwinding torque is applied to such projecting end portion while theother end portion remains secured in its fixed position relative to thequill.

Other objects and features of the invention will become apparent fromthe following more detailed description and from the drawings, in which:

FIG. 1 is an elevational view illustrating a device adapted forformation by my invention;

P18. 2 is an axial section through the helix-forming element of amachine suited for use in practicing my invention;

FIG. 3 is a fragrnental isometric view illustrating a helix in theprocess of formation;

PEG. 4 is a view similar to FIG. 3 illustrating a stage in the unwindingof the helix from the quill;

FlG. 5 is a fragmental isometric view illustrating a portion of themechanism shown in FIG. 2;

FIG. 6 is a fragmental elevation of a quill; and

PEG. 7 is a section on the line 7-7 of FIG. 6.

The device shown in FIG. 1 is of a type in common use as a support andreinforcement for a line conductor 1%. The device is formed of a lengthof wire wound into a short, close-wound coil at its middle to provide aneye 11 for attachment to any convenient support. The end portions of thewire are formed into oppositely extending aligned helices 12 which havean internal diameter such that they will grip the line conductor 1% anda pitch long enough to permit the helix to be readily wrapped around theconductor when disposed beside it.

One form of apparatus for forming the helical end portions 12 of thedevice shown in FIG. 1 is illustrated in FIG. 2. Such apparatuscomprises a stationary post 15 provided at its end with a slot 16adapted to receive 3,1719% Patented Apr. 13, 1965 the eye 11 with theaxis of such eye extending generally perpendicularly to the parallel,opposed walls of the slot. At the base of the slot 16 there is secured,as by a pin 17, a quill 13 in the form of a metal rod of circularcrosssection extending in both directions from the post 15. The quill 1%preferably has a diameter substantially equal to the outer diameter ofthe helical portions 12 and is provided with a helical groove 19corresponding in base diameter and pitch to the internal diameter andpitch of the helical portions 12.

The projecting end portions of the quill 18 are received respectively insleeves 21 and 22 mounted in fixed axial position in suitable supports23 and 24 for rotation about the axis of the quill. Each of the sleeveshas a slot 25 extending longitudinally from the sleeve-end nearest thepost 15 for a distance at least approximately equal to the length of thehelix to be formed. Each slot 25 receives the quill at its base and hasa width at least equal to the outer diameter of the helix to be formed.

In forming the specific device illustrated in FIG. 1, a length of wireis wound at its center to produce the eye 11, leaving the end portionsofthe wire extending from the eye as substantially straight legs 27(FIG. 2) diverging from each other at an angle such that they areadapted to be received in the helical groove 19 on opposite sides of thequill 18. The wire so formed is then put in place in the machine withthe eye 11 received in the slot 16 and the legs 27 received in thegroove 19 of the quill, as shown in FIG. 2. The sleeves 21 and 22 extendinto such proximity to the post 15 that the wire-legs 27 projectobliquely through the ends of the slots 25. To facilitate suchpositioning of the wire, the end of each of the sleeves 22 and 23 may beprovided with a notch 28 best shown in FIG. 5, and longitudinal edges ofthe groove 16 may be beveled as indicated at 29. The particular helices12 shown in 1G. 1 are right-hand helices; and to form them, each of thesleeves 21 and 22 will therefore rotate in a clockwise direction lookingoutward from the central post 15. In such rotation, each projectingwire-leg 27 will be engaged by the counterclockwise wall 36 of the slotand wrapped around the quill 18 into the groove 19. The notch 28 in eachsleeve 22 is located at the clockwise side of the slot 25 and shortensthe clockwise wall 31 of such slot. The length of'the notch 28 axiallyof the sleeve is desirably no greater than that necessary to facilitatepositioning of the wire at the beginning of the winding operation.

With the wire positioned as shown in FIGS. 2 and 5, the sleeves 21 and22 are rotated, each in the clockwise direction as viewed lookingoutwardly from the post 15. After approximately one-half revolution,each projecting wire-leg Z7 is engaged by a slot-wall 30, and continuedrotation of each sleeve wraps the wire about the quill into a helix inthe manner illustrated in FIG. 3. Rotation of the sleeves is terminatedwhile an end portion of each wire-leg 27 remains straight and projectingobliquely outwardly from the quill in the slot 25. When the sleeves 21and 22 are rotated in the reverse direction (FIG. 4) such projectingends of the legs 27 are engaged by the slot walls 31, and the formedhelices are unwound from the quill 18, passing radially outwardlythrough the slot 25. When both helically formed end portions 12 arecompletely unwound, the completed device is withdrawn from the machine,the eye 11 passing upwardly through the end of the slot 16.

It will be understood that my invention is not limited to machinesadapted to produce the particular support shown in FIG. 1. By laying anysubstantially straight length of wire in the quill-groove 19 so that theends of the wire project in opposite directions beyond the quill;

by holding the outer of the projecting wire-ends stationary while theother is positioned to be engaged by a side wall of the slot in thequill-surrounding sleeve, a helix corresponding in diameter and pitch tothe diameter and pitch of the groove 19 will be formed; and if thehelixforming operation is terminated while a straight end of the wirestill remains in the sleeve-slot, reverse rotation of the sleeve willunwind the completed helix from the quill.

Although I have referred to the groove 19 as corresponding in pitch andbase diameter to the pitch and internal diameter of the helix, someallowance must be made for the elastic nature of the wire, which willcause it to spring back slightly toward its original straight conditionwhen relieved of winding eifort. Accordingly, the base diameter of thegroove 19 should be somewhat less than the desired internal diameter ofthe finished helix and the pitch of the groove 19 should be somewhatless than the desired pitch of the finished helix. In some cases, aslight permanent distortion, tending to reduce the diameter of thehelix, may occur as an incident to the tin winding operation; andwhenaccurate control of helix diameter is required, any such distortion willhave to be taken into account in determining the base diameter of thequill-groove. Since the bending of the wire incident to winding of thehelix forces the wire into the base of the groove 19, the quill 18 mayhave a diameter and the slot 25 .a width greater than the outer diameterof the finished helix.

It is possible with my invention to form helices of noncircularcross-section. An example of such a helix is one adapted to grip a linecontaining a pair of parallel wires and a common insulating sheath. Toproduce a helix adapted to conform to and grip such a line, the base ofthe groove 19 may be provided at appropriate intervals with flats asshown in FIG. 7. Such flats are conveniently formed after the groove 19is cut, by grinding the base of the groove to remove the metal lyingbelow the dotted line of FIG. 7, which dotted line indicates theoriginal conformation of the groove-bottom. Because of the spring-backreferred to above, the interval between the flats 35, measured axiallyof the quill, should be somewhat more than one-half the pitch of thegroove 19 or slightly more than 180 measured angularly about the axis ofthe quill.

It may further be noted that it is unnecessary for the groove 19 to havea uniform pitch throughout its length or for the groove 19 on one sideof the post 15 to be in phase with, or of the same pitch as, the grooveon the other side. Neither is it necessary, when two helices are to besimultaneously formed, that both helices be of the same hand; for, ifdesired, I may employ a quill having helical grooves of opposite hand onopposite sides of the post 15 or its equivalent, in which event both ofthe winding sleeves would rotate in the same direction about thequill-axis in forming the two helices. Again, the invention is notlimited to an arrangement in which a single helix is formed by rotationof each of the slotted sleeves; for the quill may be provided with morethan one helical groove.

Where, as in making the device shown, two simultaneously formed heliceshave the same number of turns, it is convenient to drive the sleeves 21and 22 at the same speed from a common power-source. In such anarrangement it will of course be advisable that the sleeves be so phasedrelative to each other that both slots 25 come simultaneously intoposition to receive the wire-legs 27.

As will be apparent from the above, my invention is extremely flexiblein its capability of adaptation for the formation of helices of circularor non-circular cross-sec tion, of uniform or nonuniform pitch, and ofeither hand. It may be noted that separation of a helix from the quillby the unwinding operation which characterizes the method of myinvention is entirely different from a separation effected by unscrewingthe helix from the quill.

In my method, the progressively diminishing helix portion remaining onthe quill stays stationary with respect to the quill, whereas in thelatter method the entire helix rotates as a unit about its axis relativeto the quill. As a result, helices of graduated pitch or of non-circularcross-section cannot be removed from the quill by an unscrewingoperation; and the same is true of a unitary device embodying helices ofopposite hand formed on a unitary quill.

I claim:

1. In a method of forming a wire into a helix wherein the wire iswrapped into a helical groove provided in the outer surface of anaxially extended quill, the steps of interrupting the wrapping of thewire while an end of the wire still projects laterally from the quill,and then, by applying torque to said projecting wire-end, progressivelyunwrapping the formed helix from around the quill while maintaining theprogressively lengthening unwrapped helix portion with its axis at anacuate angle to the axis of the quill as it is bodily rotatedtherearound, a progressively lengthening portion of the quill projectingfrom within the helix between adjacent helix-turns as the unwrappingproceeds.

2. In a method of forming a wire into a helix wherein the wire iswrapped into a helical groove provided in the outer surface of anaxially extended quill, the steps of disposing the Wire in the quillgroove with one end projecting obliquely from the quill, anchoring theother end of the wire against rotation relative to the quill, wrappingthe projecting wire-end into the quill groove by applying a torque to itat a point closely adjacent to the quill to form from the wire a helixoccupying the quill-groove, and then progressively unwrapping such helixfrom around the quill and out of the quill-groove while maintaining theprogressively lengthening unwrapped helix portion with its axis at anacute angle to the axis of the quill as it is bodily rotatedtherearound, a progressively lengthening portion of the quill projectingfrom within the helix between adjacent helix-turns as the unwrappingproceeds.

3. In a method of forming a wire into a helix wherein the wire iswrapped into a helical groove provided in the outer. surface of anaxially extended quill, the steps of disposing the wire in the quillgroove with one end projecting obliquely from the quill, anchoring theother end of the wire against rotation relative to the quill, wrappingtoe projecting wire-end into the quill groove by applying a torque to itat a point closely adjacent to the quill to form from the wire a helixoccupying the quill-groove, interrupting the wrapping operation while aportion of the projecting wire-end remains unwound, and then, byapplying torque to said unwound portion, progressively unwrapping theformed helix from around the quill while maintaining the progressivelylengthening unwrapped helix portion with its axis at an acute angle tothe axis of the quill as it is bodily rotated therearound, aprogressively lengthening portion of the quill projecting from withinthe helix between adjacent helix-turns as the unwrapping proceeds.

4. In a method of forming the end portions of a length of wire intohelices, the steps of securing the intermediate portion of the wireadjacent the intermediate portion of an extended quill having endportions provided with helical grooves, wrapping the end portions of thewire into the helical grooves of the quill to form them into helices,interrupting the wrapping of the wire while the ends of the wire remainunwrapped, and then, by applying torque to the unwrapped ends,progressively unwrapping each formed helix from around the quill whilemaintaining the progressively lengthening unwrapped portion of the helixwith its axis at an acute angle to the axis of the quill as it is bodilyrotated therearound, a progressively lengthening portion of the quillprojecting from within the helix between adjacent helix-turns as theunwrapping proceeds.

5. A method of forming a wire into a helix, comprising wrapping the wireinto a helical groove in the outer surface of an axially extendingquill, interrupting the winding when a helix of the desired length hasbeen thus produced, and then, by applying an unwinding torque atopposite ends of the helix, progressively unwrapping the formed helixfrom around the quill while maintaining the progressively lengtheningunwrapped helix portion with its axis at an acute angle to the axis ofthe quill as it is bodily rotated therearound, a progressivelylengthening portion of the quill projecting from within the helixbetween adjacent helix-turns as the unwrapping proceeds. 10

References Cited by the Examiner UNITED STATES PATENTS 1,228,031 5/ 17Kriesel 140-90 2,209,114 7/40 Dorr 153-66 2,898,952 8/59 Lovecky l40l24MICHAEL V. BRINDISI, Primary Examiner.

CHARLES W. LANHAM, KINGSLEY CONGDON PECK, Examiners.

1. IN A METHOD OF FORMING A WIRE INTO A HELIX WHEREIN THE WIRE ISWRAPPED INTO A HELICAL GROOVE PRODIVED IN THE OUTER SURFACE OF ANAXIALLY EXTENDED QUILL, THE STEPS OF INTERRUPTING THE WRAPPING OF THEWIRE WHILE AN END OF THE WIRE STILL PROJECTS LATERALLY FROM THE QUILL,AND THEN, BY APPLYING TORQUE TO SAID PROJECTING WIRE-END, PROGRESSIVELYUNWRAPPING THE FORMED HELIX FROM AROUND THE QUILL WHILE MAINTAINING THEPROGRESSIVELY LENGTHENING UNWRAPPED HELIX PORTION WITH ITS AXIS AT ANACUATE ENGLE TO THE AXIS OF THE QUILL AS IT IS BODILY ROTATEDTHEREAROUND, A PROGRESSIVELY LENGTHENING PORTION OF THE QUILL PROJECTINGFROM WITHIN THE HELIX BETWEEN ADJACENT HELIX-TURNS AS THE UNWRAPPINGPROCEEDS.